Patent GB-368257-A (GB)
Title: Improvements in the conversion of hydrocarbons
IPC: B01J19/00
Filed: 1930-10-27
Abstract: The conversion of fluid hydrocarbons by heat treatment at temperatures over 350 DEG  C. is effected in reaction chambers of which the walls are constructed of non-metallic refractory material wholly or partly coated on the inside with a glaze of an inorganic substance, preferably comprising a silicate, phosphate, or borate of an alkali or alkaline earth metal or of copper, manganese, lead, or chromium.  Suitable refractory materials of which the reaction chamber walls may be constructed are chamotte or materials containing large amounts of silicon carbide, for example, those known under the Trade Marks "Karrellite" or "Stellacarbide."  Only such parts of the apparatus as are exposed to the reaction temperatures may be coated. The reaction space may be wholly or partly filled with pieces of refractory material such as chamotte also provided with an inorganic glaze. Catalysts such as silicides or carbides may be added to the coatings.ALSO:The conversion of fluid hydrocarbons by heat treatment at temperatures over 350 DEG  C., except the production of diolefines by decomposition of cyclic or acyclic paraffins or higher olefines, is effected in reaction chambers of which the walls are constructed of non-metallic refractory material wholly or partly coated on the inside with a glaze of an inorganic substance, preferably comprising a silicate, phosphate, or borate of an alkali or alkaline-earth metal or of copper, manganese, lead, or chromium.  Suitable refractory materials of which the reaction chamber walls may be constructed are chamotte or materials containing large amounts of silicon carbide, for example, those known under the Trade Marks "Karrellite" or "Stellacarbide." The substance forming the glaze, or its components, are applied to the material walls in the cold, and the glaze produced by treating to such an extent that sintering or fusion occurs, castings impermeable to gases and preventing injurious deposition of carbon up to temperatures above 1000 DEG  C. being thus obtained. Only such parts of the apparatus as are exposed to the reaction temperatures may be coated.  The reaction chamber may be wholly or partly filled with pieces of material, preferably refracting material such as chamotte, also provided with an inorganic glaze, for example, in a Cowper apparatus when working discontinuously the filling may be of chamotte coated in this manner.  Catalysts such as silicates or carbides may be added to the coatings. According to examples (1) chamotte is coated with sodium calcium silicate and heated to about 1200 DEG  C.  This material is introduced into a chamotte tube provided with an internal coating in the same way, through which methane is then passed at 1050 DEG  C.  A condensate consisting mainly of benzene and a residual gas containing olefines and hydrogen are obtained; (2) a mixture of ethane, propane and butane is led at 850 DEG  C. through a chamotte tube as in (1), a condensate containing benzene and a residual gas containing methane, ethylene and higher olefines being obtained; (3) a Cowper apparatus is filled with chamotte plates, the walls and filling having been previously covered by squirting with a paste comprising feldspar, fluorspar, and quartz, and heated to 1400 DEG  C.  Methane is led there-through at 1100 DEG  C., a condensate containing benzene and a residual gas containing olefines and hydrogen being obtained; (4) methane is passed at 1050 DEG  C. through a porcelain tube coated with a glaze formed from a mixture of silicic acid, lead oxide, and sodium and potassium silicates.  A benzene condensate is obtained, and the residual gas may be treated again; and (5) methane is treated as in (4) in a porcelain tube coated internally with a chromium silicate glaze formed from chromium oxide and glass powder.  Specifications 317,359, [Class 2 (iii), Dyes &c.], and 320,619, [Class 32, Distilling &c.], are referred to.